Lever apparatus having stationary fulcrum, movable force point and movable action point, and machine which incorporates the same

ABSTRACT

A fulcrum of a lever member which is rotatably supported by a stationary shaft has force and action points provided with a force point regulator and an action point regulator, respectively. Each of the regulators has a roller and a pair of guide plates guiding the roller between the guide plates as the lever member is rotated about the fulcrum supported by the stationary shaft.

TECHNICAL FIELD

The present invention relates to a lever apparatus having a stationaryfulcrum, a movable force point and a movable action point, and also to amachine which incorporates the same.

BACKGROUND ART

A lever apparatus is widely used in the field of machinery, such asmachine tools and industrial machines, and in the power transmissionportions of moving mechanisms of structures of various types. FIGS. 1and 2 show examples of a power transmission mechanism that utilizes theprinciples of a lever.

In the example shown in FIG. 1, pin links 13 and 14 are provided for thecircumferential portions of a disk 12 rotatable with a stationaryfulcrum as a center, such that the pin links 13 and 14 are apart fromeach other by 90°. The pin link 13 serving as a force point is coupled,through a coupling member 15a extending in a tangential direction of thedisk 12, to one end of a driving arm 17 supported by a support shaft 16.The other end of the driving arm 17 is coupled through a driving link 18to a driving section. The pin link 14 serving as an action point iscoupled, through a coupling member 19a extending in a tangentialdirection of the disk 12, to the tip end of a driven section 22 of ahydraulic device 21 supported by a support shaft 20.

In the example shown in FIG. 1, the linear motion of the driving link 18rotates the driving arm 17, and power is transmitted through thecoupling member 15a to the disk 12 (i.e., a lever apparatus) and isfurther transmitted through the coupling member 19a to the hydraulicdevice 21. However, the pin links 13 and 14, respectively serving as aforce point and an action point, describe an arc when the disk 12 isrotated. Thererover each of the coupling members 15a and 19a does notlinearly reciprocate but swings widthwise. In other words, the lineardriving force of the driving link 18 cannot be transmitted to thecoupling member 19 as a linear operating force.

In the example shown in FIG. 2, where a fulcrum 23 is fixed and a forcepoint 24 is lowered, an action point roller 25 is strained in such amanner as to bend a coupling member 19b in the indicated direction. Whenthis type of device is used for a long time, those portions of a guide26 which are depicted as being upper left and lower right portions withreference to a guide hole are likely to be abraded.

SUMMARY OF INVENTION

Accordingly, an object of the present invention is to provide a leverapparatus which is supported at a stationary fulcrum, which employsregulators permitting coupling members respectively connected to theforce and action points to linearly reciprocate at all times, and whichenables a large force to be transmitted in a desired direction with highprecision, and also to provide a machine incorporating the leverapparatus.

According to the present invention, this object is achieved by employingregulators which swing and displace the force and action points of alever apparatus without reference to the rotational position of thelever apparatus in such a manner that the arcuate loci of the force andaction points are converted into linear reciprocating motions easily andaccurately.

A machine incorporating the lever apparatus of the present invention(e.g., a pressing machine) comprises: a lever member which is rotatablysupported by a stationary fulcrum; regulators including guide membersfor swinging and displacing the force and action points of the levermember; a driving mechanism, coupled to the lever member, fortransmitting a driving force to the force point of the lever member; anda tool section (e.g., a pressing head) coupled to the action point ofthe lever member and driven in accordance with the movement of the levermember.

The inventor of the present invention developed lever apparatuseswherein a fulcrum is moved in accordance with the rotation of a levermember, and filed patent applications to seek patents for such leverapparatuses. One of the patent applications was PCT internationalApplication No. PCT/JP90/00737 filed on Jun. 6, 1990 (now U.S. Pat. No.5,182,967). In the lever apparatus of this International Application,the fulcrum is moved in accordance with the rotation of the lever memberin such a manner that the force point and the action point can be movedwith a high degree of freedom, as a result of which the force point andthe action point describe linear lines. However, it is obvious that thelever apparatus will become more mechanically stable and precise andsimpler in structure, if the lever member of the apparatus is supportedon a stationary fulcrum. In consideration of this, the present inventionemploys a lever member rotatably supported on a stationary fulcrum, andfurther employs regulators including guide members for moving anddisplacing the force and action points of that lever member. Owing tothe employment of these, the present invention can provide a levermember which is mechanically stable and in which the force point and theaction point are permitted to move with a high degree of freedom, andcan further provide a machine incorporating the lever apparatus.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram showing a power transmission mechanismemploying a conventional lever apparatus;

FIG. 2 is a schematic diagram showing another power transmissionmechanism employing a conventional lever apparatus;

FIG. 3 is a perspective view schematically showing a lever apparatusaccording to one embodiment of the present invention;

FIG. 4 is a diagram showing a modification of the embodiment depicted inFIG. 3;

FIG. 5 shows an example of a three-dimensional power transmissionmechanism using the embodiment depicted in FIG. 4;

FIG. 6 is a schematic view showing a lever apparatus according toanother embodiment of the present invention;

FIG. 7 is a diagram schematically showing a lever apparatus according tostill another embodiment of the present invention;

FIG. 8 is a diagram schematically showing a lever apparatus according toa further embodiment of the present invention;

FIG. 9 is a diagram schematically showing a lever apparatus according toa further embodiment of the present invention;

FIG. 10 is a diagram showing the loci described by the force and actionpoints of the embodiment depicted in FIG. 6;

FIG. 11 is a diagram showing the loci described by the force and actionpoints of the embodiment depicted in FIG. 8;

FIG. 12 is a schematic diagram showing a lever apparatus according tostill another embodiment of the present invention;

FIG. 13 is a schematic diagram showing a lever apparatus according to afurther embodiment of the present invention;

FIG. 14 is a schematic diagram showing a lever apparatus according to astill further embodiment of the present invention;

FIG. 15 is a schematic diagram showing a lever apparatus according toanother embodiment of the present invention;

FIG. 16 is a schematic diagram showing a lever apparatus according to afurther embodiment of the present invention;

FIG. 17 is a schematic diagram showing a lever apparatus according to astill further embodiment of the present invention;

FIG. 18 shows a pressing machine incorporating a lever apparatus of thepresent invention;

FIG. 19 shows a surface grinding machine incorporating a lever apparatusof the present invention;

FIG. 20 is a perspective view schematically showing an example in whicha lever apparatus of the present invention is incorporated in a damperof a building;

FIG. 21 is a schematic view showing the case where a lever apparatus ofthe present invention is incorporated in a diaphragm pump;

FIG. 22 shows an embodiment wherein a lever apparatus of the presentinvention is incorporated in an X-Y table driving mechanism; and

FIG. 23 is a diagram showing the loci described by the major portions ofthe structure depicted in FIG. 22.

DETAILED DESCRIPTION

Embodiments of the present invention will now be described in detail.

Referring to FIG. 2, a plurality of pin links 33a, . . . 33h areprovided for the circumferential portions of a disk 32 rotatable with astationary fulcrum 31 as a center, such that the pin links are apartfrom one another by predetermined angles. Of the two pin links 33b and33d which are apart from each other by 90°, the pin link 33b serving asa force point is coupled to a driving section (not shown) throughcoupling members 35a and 35b extending in a tangential direction of thedisk 32. Coupling member 35b is restricted in movement by a guide 36such that it linearly moves in a circumferential direction of the disk32. The pin link 33d serving as an action point is coupled to a drivensection (not shown) through coupling members 37a and 37b extending in atangential direction of the disk 32. Coupling member 37b is restrictedin movement by a guide 38 such that it linearly moves in acircumferential direction of the disk 32. The coupling member 35a whichengages with the pin link 33b serving as the force point is made toserve as a regulator by forming an elongated hole L1 therein; likewise,the coupling member 37a which engages with the pin link 33d serving asthe action point is also made to serve as a regulator by forming anelongated hole L2 therein. Shafts 35b and 37b linearly reciprocatethrough guides 36 and 38, respectively. The ranges of movement which canbe converted by the regulators 35a and 37a are determined by the lengthsW of the elongated holes L1 and L2. It should be noted that the centralaxes extending in the length (W) direction of the elongated holes L1 andL2 of the coupling members 35a and 37a (which are regulators for theforce and action points, respectively) must be perpendicular to theshafts 35b and 37b, so as to enable power to be transmitted without anyloss with this structure, the linear movement of the shaft 35b connectedto the force point is converted into the linear movement of the shaft37b connected to the action point with high efficiency. When thedistance between pin link 33b and the stationary fulcrum 31 and thedistance between pin link 33d and the stationary fulcrum 31 are equal toeach other, the power transmission ratio is 1:1. Needless to say, thepower transmission ratio can be arbitrarily determined by changing thesedistances.

FIG. 4 shows a power transmission mechanism of 90° angle type, whereinthe power transmission ratio is 1:1. Referring to FIG. 4, a lever arm 42is rotatable about a fulcrum 41, which is secured to a housing 40attached to a frame (not shown). The lever arm 42 is substantially inthe shape of a right-angled triangle and has two pins 42a and 42b. Thetwo pins 42a and 42b are apart from each other by 90° and located awayfrom the fulcrum 41 by the same distance. Support plates 43a and 43b areattached to the housing 40. The support plates 43a and 43b holdinput/output shafts 44a and 44b in such a manner that the input/outputshafts 44a and 44b can freely move in tangential directions of thecircle described by the pins 42a and 42b. Coupling members 45a and 45bare coupled, at one end, to the distal ends of the shafts 44a and 44b.Elongated holes 46a and 46b are formed at the other ends of the couplingmembers 45a and 45b, and the pins 42a and 42b engage with the elongatedholes 46a and 46b, respectively. In this manner, a power transmissionmechanism 47 employing a lever apparatus of the present invention isobtained.

Referring to FIG. 4, when input/output shaft 44b is applied with a forceacting in the direction which is "upward" in the FIGURE, the lever arm42 is rotated counterclockwise, and input/output shaft 44a is linearlymoved in the direction perpendicular to input/output shaft 44b. In thiscase, the pin 42b to which the force is input serves as a force point,while the pin 42a from which the force is output serves as an actionpoint. It should be noted that the power transmission mechanism 47 shownin FIG. 4 is a reversible type, and pin 42a and pin 42b may be made toserve as force and action points, respectively.

FIG. 5 shows an example of a three-dimensional power transmission systememploying a number of power transmission mechanisms depicted in FIG. 4.In the example shown in FIG. 5, three power transmission mechanisms 47A,47B and 47C are arranged three-dimensionally on a frame (not shown), anda force can be transmitted in any of the three-dimensional directions.Since the power transmission loss in each of the power transmissionmechanisms is substantially zero, the force applied to an input shaft44c can be transmitted to an output shaft 44d without being damped, andis then exerted on a driven section 48.

In the embodiment shown in FIG. 4, the coupling members 49a and 45b,having elongated holes 46a and 46b with which pins 42a and 42b are inengagement, are employed as a force point regulator and an action pointregulator, respectively. However, the present invention is not limitedto this, and various means can be employed as the force point regulatorand action point regulator.

FIGS. 6 through 9 show other embodiments of the present invention.

In FIGS. 6 through 9, reference numeral 51 denotes a lever member,reference numeral 52 denotes a fulcrum member for fixedly supporting thelever member 51, reference numeral 53 denotes a fulcrum support memberfor supporting the fulcrum member 52, reference numeral 54 denotes aforce point regulator which is coupled to a force point (i.e., one endof the levee member 51) in such a manner that the force point regulatoris rotatable and displaceable, and reference numeral 56 denotes anaction point regulator which is coupled to an action point (i.e., theother end of the lever member 51) in such a manner that the action pointregulator is rotatable. The coupling portion for coupling the forcepoint regulator 54 to the lever member 51 is preferably a known camfollower type comprising a roller that rolls between a pair of guideplates 55a and 55b.

The embodiments shown in FIGS. 6 through 9 are of a type wherein theforce point regulator 54 and the action point regulator 56 are linearlymovable in the vertical direction along the grooves of guide frames 58.The action point regulator 56 has a similar structure, and a roller 56cis supported between a pair of guide members 56a and 56b such that it islinearly rollable in the horizontal direction.

The embodiments shown in FIGS. 6 and 7 are of an intermediate fulcrumstructure wherein the fulcrum member 52 is located between the forcepoint 54 and action point 56 of the lever member 51. In the embodimentshown in FIG. 6, the action point regulator 56 operates such that theinput/output shafts 44a and 44b are linearly moved in the verticaldirection. When the force point regulator 54 is driven in the verticaldirection, the lever member 51 swings, with the fulcrum member 52 as acenter. Since the fulcrum member 52 of the lever member 51 isstationary, the rollers 55c and 56c move along the guide members 55a,55b, 56a and 56b and describe arcuate loci, when the lever member 51swings. However, the force point regulator 54 and action point regulator56 move linearly in the vertical direction. In the case of theembodiment shown in FIG. 7, the action point regulator 56 is linearlymoved in a slanted direction.

In this manner, the force point and action point of the lever apparatusdepicted in FIG. 6 can describe linear loci, as indicated in FIG. 10.

The embodiment shown in FIG. 8 is of an outer fulcrum structure whereina stationary fulcrum member 52 and a force point regulator 54 arelocated at the opposite ends of a lever member 51 and wherein an actionpoint regulator 56 is located at an intermediate point of the levermember 51. In this case, the stroke of the action point is shorter thanthat of the force point, but an increased force is exerted at the actionpoint.

In the embodiment shown in FIG. 9, a stationary fulcrum member 52 and anaction point regulator 56 are located at the opposite ends of a levermember 51, and a force-application regulator 54 is located at anintermediate point of the lever member 51. In this case, the stroke ofthe action point is longer than that of the force point, but a decreasedforce is exerted at the action point.

According to these embodiments, when the lever member 51 swings, therollers 55c and 56c freely move between the guide plates in accordancewith the movements of the force point regulator 54 and the action pointregulator 56. Therefore, the force point regulator 54 and the actionpoint regulator 56 have high degrees of freedom when they move. Inaddition, the rollers 55c and 56c of the action point regulator 56 andforce point regulator 54 can move to their optimal positions.Accordingly, a driving force can be efficiently transmitted from theforce point regulator 54 to the action point regulator 56 through thelever member 51, with the action point regulator 56 being permitted tomove in various ways.

The movement of the force point regulator 54 and the movement of theaction point regulator 56 may be any combination of a vertically linearmovement, a horizontally linear movement and a slantwise linearmovement.

The lever apparatuses of movable force and action points type, whichhave structures described above, have a wide range of application; theycan be employed in machine tools (such as a pressing machine) andindustrial machines, and in the movable portions of structures ofvarious types.

In the lever apparatus shown in FIG. 6, the force point and the actionpoint are made movable by permitting the rollers 55c and 56c of theforce point regulator 54 and action point regulator 56 to roll betweenthe guide plates 55a, 55b, 56a and 56b.

In the examples shown in FIGS. 12 and 13, no roller is employed.Instead, sliding members 55c and 56c, which are inserted between theguide members 55a, 55b, 56a and 56b of a movable force point regulator54 and a movable action point regulator 56, have holes, and the forcepoint and action point of a lever member 51 are movably coupled togetherby means of shafts 55d and 56d inserted into the holes of the slidingmembers 55c and 56c. In the example shown in FIG. 13, sliding members55C1 and 55C2, which are inserted in the guide grooves 55AG and 55BG ofguide members 55A and 55B, have holes, and one end of a lever member 51is movably coupled by means of a shaft 55d inserted into the holes ofthe sliding members 55C1 and 55C2.

The force point regulator 54 and the action point regulator 56 arerespectively connected to coupling members 44a and 44b, and members 44aand 44b are respectively inserted in guide plates 43a and 43b secured tothe ground, such that they move linearly. In the examples, the outersurfaces of the sliding members 55c, 56c, 55C1 and 55C2 are worked withhigh precision, and the inner surfaces of guide plates 55a, 55b, 56a,56b, 55A and 55B are worked to be smooth. By this working, no largefriction is produced, and the examples can be put to practice withoutcausing any particular problem. In the example shown in FIG. 12, inparticular, the forces applied to the shafts 44a and 44b are transmittedat right angles at all times, so that the torsion stress occurring inthe case depicted in FIG. 2 is not produced in the examples.

In order to permit the sliding members 55c, 56c, 55C1 and 55C2 to movefurther smoothly, a number of ball bearings may be inserted between theguide plates 55a, 55b, 56a and 56b and the sliding members 55c and 56c,and also in the upper and lower gaps between the guide grooves 55AG and55BG and the sliding members 55C1 and 55C2, as shown in FIGS. 14 and 15.Rollers may be employed in place of the ball bearings.

FIGS. 16 and 17 each show other examples of a movable force and actionpoints structure. In the example shown in FIG. 16, shafts 55d and 56dare attached to regulator support members 74a and 74b, respectively, anda lever member 51 is swingably supported on a stationary fulcrum shaft52. The support members 74a and 74b are inserted into bearing groovesformed in the upper portions of the guide plates 55b and 56b, and arepermitted to move in the directions indicated by the arrows, due to anumber of ball bearings 75 provided between the support members 74a and74b and the guide plates 55b and 56b.

In the example shown in FIG. 17, the force point of the lever member 51is movably supported by the regulator shaft 55d, and the support member74a is placed on the guide plate 55b, with linear rails 76 locatedtherebetween. A movable force point is obtained by supporting one end ofthe lever member 51 on the support member 74a in such a manner as to bemovable in the direction in which the rails extend.

FIG. 18 shows a pressing machine which incorporates the lever apparatusdepicted in FIG. 6 and which comprises a movable force point and amovable action point. In the pressing machine shown in FIG. 18, a levermember 51 is movably supported by a fulcrum shaft 52 provided for afulcrum member 53.

One end of the lever member 51 is coupled to a vertical driving shaft 80through a force point regulator 54. The lower end of the verticaldriving shaft 80 is coupled to an eccentric shaft 84 through a crankmechanism 82, and is driven in the vertical direction in accordance withthe rotation of the eccentric shaft 84. One end of the eccentric shaft84 is coupled to an electric motor 88 through a power transmissionmechanism 86 (e.g., a gear mechanism), and is rotated by the electricmotor 88.

The other end of the lever member 51 is coupled to an elevator 90through an action point regulator 56. The head 92 attached to theelevator 90 is driven in the vertical direction, as indicated by thearrow. In the case of this embodiment, the torque of the electric motor88 is transmitted to the lever apparatus via each link mechanism, and itis not necessary to employ a flywheel or the like, such as that requiredin the conventional art. Accordingly, the machine is small in size, andthe lever apparatus incorporated therein and comprising a movable forcepoint and a movable action point enables power to be smoothlytransmitted to the head 92.

FIG. 19 shows an example illustrating how the present invention isapplied to a surface grinding machine wherein the strokes of movableforce and action points are adjustable by a movable fulcrum.

Referring to FIG. 19, a bed 100 is supported on a support member 102,with bearings 104 interposed, such that the bed 100 can smoothly move onthe support member 102 in a horizontal plane. The lower portion of thebed 100 is supported by one end of a lever member 108 by means of both ashaft 106 (which serves as an action point) and a linearly movablebearing mechanism 107. The lever member 108 is coupled to a fulcrummember 112 which is in engagement with a screw rod 110. The fulcrummember 112 is rotatably supported on the ground G. The screw rod 110 iscoupled through a gear device 114 to the rotating shaft of a motor 116attached to the lever member 108.

The other end of the lever member 108 is coupled to a linearly movablebearing mechanism 120 through a shaft 118 (which serves as a forcepoint). The linearly movable bearing mechanism 120 is coupled to a servomotor 126 through both a crank shaft 122 and a crank mechanism 124.

In the structure mentioned above, the torque of the servo motor 126 isconverted into a linear movement by means of the crank mechanisms 122and 124, and the linear movement is transmitted to the shaft 118 (theforce point). Due to the movable force point 118 and the movable actionpoint 106, the lever member 108 swings, with the fulcrum member 112 as acenter, and the bed 100 is smoothly moved in the horizontal direction.

When the motor 116 is turned on, the screw rod 110 is rotated by thegear device 114, and the position of the fulcrum 112 is moved. Since thedistance between the fulcrum 112 and shaft 106 and the distance betweenthe fulcrum 112 and shaft 118 are changed, the moving stroke of the bed100 is changed, accordingly.

FIG. 20 shows an embodiment wherein a lever apparatus of the presentinvention is applied to a damper of a building. A crank shaft 122similar to that employed in the example depicted in FIG. 19 is coupledto a crank mechanism and a servo motor (neither is shown) through ashaft support member 130. One end of a lever member 134 (i.e., the endserving as a force portion) is coupled to one end of the crank shaft 122through a cam follower mechanism 132 (which serves as a force pointregulator). A stationary fulcrum 136 is located at the central point ofthe lever member 134, and the other end of the lever member 134 (i.e.,the end serving as an action point regulator) is coupled to a damperblock 140 through a cam follower mechanism 138. The damper block 140 ismovably supported on linear rails 142a and 142b. The linear rails 142aand 142b are installed, for example, on a story which is substantiallythe vertical center of a multistory building and at such a position aswould shake most intensely at the time of an earthquake.

In general, the vibration of an earthquake is several cycles per second,and it is easy to move the damper block 140 at a speed on this order. Inthe conventional art, the damper block 140 is moved by a feed screw typemechanism, so that it cannot be moved at high speed in response to theearthquake. In addition, since the block 140 is considerably heavy, thefeed screw does not have a sufficient mechanical strength. Therefore,the conventional art does not ensure a satisfactory damping effect. Inthis embodiment, the lever apparatus and the linear rails 142a and 142bare combined, and the combination has brought about a very satisfactoryresult.

FIG. 21 shows an example in which a lever apparatus of the presentinvention is incorporated in the driving mechanism of a diaphragm pump.Referring to FIG. 21, a lever member 171 is applied with torque in thedirection indicated by the arrow from a force point regulator 170 of camfollower type. Upon application of the torque, the lever member 171swings, with a stationary fulcrum 172 as a center, and the diaphragm 175of the diaphragm pump is vertically driven by means of a coupling member174 connected to an action point regulator 173.

FIG. 22 shows an example of an X-Y table incorporating a movable forceand action points type lever apparatus of the present invention. In thisexample, a table 180 is designed to move in the X direction along rails182a and 182b. Since the table 180 can be moved in the Y direction in asimilar manner, the mechanism for movement in this direction is omitted.The table 180 is pivotally supported by one end of a lever member 186 bymeans of an action point regulator 184. At the other end of the levermember 186, rollers 194, which are contained in a regulator 190 andserve as the force point of a ball screw rotation feed mechanism 192,are provided, with a stationary fulcrum 188 and an action pointregulator 190 being located between the rollers 194 and the action pointregulator 184. A guide member 196 is in threadable engagement with aball screw 200 driven by a motor 198.

FIG. 23 shows the loci of the major portions of the structure depictedin FIG. 22. When the ball screw 200 is fed, for example, in units of 10μm, the action point regulator 180 is moved (i.e., the table 180 ismoved) in units of 2 μm. The rollers 194 serving as the force point rollon the guide member 196 while describing an arcuate locus. When the boltscrew 200 is fed by 80 μm, the action point regulator 184 moves for adistance of 16 μm (=80/5).

Where the X-Y table has such a structure as mentioned above, the table180 can be driven with very considerably high accuracy. Therefore, theX-Y table can be employed, for example, in an exposure device forsemiconductor wafers.

I claim:
 1. A lever apparatus comprising:a lever member having a fixedfulcrum, a moving force point and an action point; means for rotatablysupporting said fixed fulcrum at a stationary point; a force pointregulator including a roller rotatably mounted at said force point, anda pair of guide plates for rollably supporting the roller therebetween;first means for linearly moving the pair of guide plates of said forcepoint regulator while guiding the roller in the pair of guide platesalong a rotation locus of said force point about said fixed fulcrum; anaction point regulator including a roller rotatably mounted at saidaction point, and a pair of guide plates for rollably supporting theroller of said action point regulator therebetween; and second means forlinearly moving the pair of guide plates of said action point regulatorwhile guiding the roller of the action point regulator in the guideplates of the action point regulator along a rotation locus of saidaction point about said fixed fulcrum.
 2. A pressing machinecomprising:a lever apparatus including:lever member having a fixedfulcrum, a moving force point and an action point; means for rotatablysupporting said fixed fulcrum at a stationary point; a force pointregulator including a roller rotatably mounted at said force point, anda pair of guide plates for rollably supporting the roller therebetween;first means for linearly moving the pair of guide plates of said forcepoint regulator while guiding the roller in the pair of guide platesalong a rotation locus of said force point about said fixed fulcrum; anaction point regulator including a roller rotatably mounted at saidaction point, and a pair of guide plates for rollably supporting theroller of said action point regulator therebetween; and second means forlinearly moving the pair of guide plates of said action point regulatorwhile guiding the roller of the action point regulator in the guideplates of the action point regulator along a rotation locus of saidaction point about said fixed fulcrum; a driving mechanism coupled tosaid force point regulator for transmitting linearly a driving force tosaid lever member via said force point; and a head coupled to saidaction point regulator so as to be driven linearly in accordance with amovement of said lever member.
 3. A lever apparatus comprising:a levermember having a fixed fulcrum, a moving force point and an action point;means for rotatably supporting said fixed fulcrum at a stationary point;a force point regulator including a slider rotatably mounted at saidforce point, and a pair of guide plates for movably supporting theslider therebetween; first means for linearly moving the pair of guideplates of said force point regulator while guiding the slider in thepair of guide plates along a rotation locus of said force point aboutsaid fixed fulcrum; an action point regulator including a sliderrotatably mounted at said action point, and a pair of guide plates formovably supporting the slider of said action point regulatortherebetween; and second means for linearly moving the pair of guideplates of said action point regulator while guiding the slider in thepair of guide plates along a rotation locus of said action point aboutsaid fixed fulcrum.
 4. A pressing machine comprising:a lever apparatusincluding:a lever member having a fixed fulcrum, a moving force pointand an action point; means for rotatably supporting said fixed fulcrumat a stationary point; a force point regulator including a sliderrotatably mounted at said force point, and a pair of guide plates formovably supporting the slider therebetween; first means for linearlymoving the pair of guide plates of said force point regulator whileguiding the slider in the pair of guide plates along a rotation locus ofsaid force point about said fixed fulcrum; an action point regulatorincluding a slider rotatably mounted at said action point, and a pair ofguide plates for movably supporting the slider of said action pointregulator therebetween; and second means for linearly moving the pair ofguide plates of said action point regulator while guiding the slider ofthe action point regulator in the guide plates of the action pointregulator along a rotation locus of said action point about said fixedfulcrum; a driving mechanism coupled to said force point regulator fortransmitting linearly a driving force to said lever member via saidforce point; and a head coupled to said action point regulator so as tobe driven linearly in accordance with a movement of said lever member.